Tangent roll dressing for two axially spaced grinding wheels

ABSTRACT

A conventional pair of left- and right-hand grinding wheels are rotatably supported in a centerless grinder with an axial spacing therebetween dictated by the setup requirements of the workpiece to be ground. A driven roll dresser is movable inwardly in a tangential direction and into tangential contact with an axially extending portion of the left-hand wheel to dress not only that portion of the wheel periphery, but also the peripheral edge of the left-hand wheel which faces the right-hand wheel. The tangential dresser has left- and right-hand end portions for successively dressing the left- and right-hand grinding wheels, and an intermediate portion for dressing the facing peripheral edges thereof.

United States Patent [72] lnventors Rudolph A. Mattson [45] Patented [73] Assignee June l5, 1971 Universal American Corporation Springfield, Mass.

[54] TANGENT ROLL DRESSING FOR TWO AXIALLY SPACED GRINDING WHEELS 4 Claims, 2 Drawing Figs.

[52] U.S. Cl 51/283, 125/1 1 [5i] lnt.Cl B24!) 1/00, B24b 53/00 [50] Field otSearch l25/ll; 51/283 References Cited UNITED STATES PATENTS 3,407,800 lO/l968 Hoare .r 125/11 2,730,85l l/l956 wallaceflu l25/llX 2,586,755 2/1952 Wilson 125/1 1X Primary Examinerl-larold D. Whitehead Attorney-McCormick, Paulding and Huber ABSTRACT: A conventional pair of leftand right-hand grinding wheels are rotatably supported in a centerless grinder with an axial spacing therebetween dictated by the setup requirements of the workpiece to be ground. A driven roll dresser is movable inwardly in a tangential direction and into tangential contact with an axially extending portion of the lefthand wheel to dress not only that portion of the wheel periphery, but also the peripheral edge of the left-hand wheel which faces the right-hand wheel. The tangential dresser has leftand right-hand end portions for successively dressing the leftand right-hand grinding wheels, and an intermediate portion for dressing the facing peripheral edges thereof.

PATENTEDJUMSIQYI 3'584'425 INVENTORS FREDERICH F GROLL RUDOLPH A. MATT ATTORNEYS TANGENT ROLL DRESSING FOR TWO AXIALLY SPACED GRINDING WHEELS SUMMARY OF INVENTION This invention relates to roll dressing of grinding wheels, and deals more particularly with a method for successively dressing a pair of axially spaced grinding wheels by moving a single dresser roll along predetermined parallel paths oriented tangentially with respect to these wheels, with the result that a single roll dresser can be used to dress both grinding wheels despite changes in the axial spacing between these wheels.

An object of the present invention is to provide a method for dressing two axially spaced grinding wheels through the use of a single impregnated roll dresser which is adapted to follow a particular path so that portions thereof tangentially dress both grinding wheels.

A more specific object of the present invention is to provide tangent roll dressing of the foregoing character wherein the roll dresser has leftand right-hand end portions which successively engage first one and then the other of said grinding wheels in a compound motion which includes moving the roll dresser tangentially with respect to each wheel, and also axially with respect thereto for imparting to these wheels a positive cylindrical roll dressing action.

BRIEF DESCRIPTION OF DRAWING FIG. 1 is a plan view of a pair of axially spaced grinding wheels of the type normally provided on a common shaft to grind spaced portion of workpiece in a centerless grinder; and also shows a tangent roll dresser in successive positions in solid and in broken lines respectively, with arrows to indicate its complete path of movement.

FIG. 2 is a vertical sectional view through the left-hand grinding wheel shown in FIG. 1 being taken on line 2-2 of that figure.

DETAILED DESCRIPTION In a centerless grinding machine, workpiece setup requirements often dictate that two axially spaced grinding wheels be arranged for grinding the opposed end portions of the workpieces to a particular diameter. Furthermore, the axial spacing between these grinding wheels usually varies to accommodate a range of workpiece sizes. The axial spacing between the grinding wheels can be varied for accommodating workpieces of various axial length and present day machines permit this to be done. The primary purpose of the present invention is to provide a method for dressing such grinding wheels with a single roll dresser which is adapted to follow a compound motion as indicated schematically in FIG. 1.

FIG. 1 shows two axially spaced grinding wheels and 12 adapted for rotation on a common axis 14 to grind workpieces (not shown) having opposed end portions with a predetermined axial spacing therebetween. In accordance with the present invention a roll dresser I6 is adapted to move successively into tangential contact with each of the grinding wheels 10 and 12 in such a manner that leftand right-hand portions 18 and 20 of the roll dresser serve to successively face or dress the grinding wheels 10 and 12 respectively.

The roll dresser 16 also includes an intermediate portion 22 of somewhat larger diameter then the cylindrical end portions, 18 and 20, and it is an important feature of the present invention that concave flared portions 24 and 26 serve to join the raised intermediate portion 22 to the leftand right-hand cylindrical end portions 18 and 20. These concave portions 24 and 26 serve to face or dress the peripheral edges 28 and 30 of the grinding wheels 10 and 12 respectively. It will be apparent that the particular contour provided in the areas 24 and 26 of the roll dresser 16 will be dictated by the desired shape of the edges 28 and 30 of the leftand right-hand grinding wheels 10 and 12 respectively.

In carrying out the method of the present invention the roll dresser 16 is moved from a rest position, indicated in full lines in FIGS. 1 and 2, generally tangentially inwardly in the direction of the arrow 32 to the broken line position wherein the left-hand end portion 18 of the roll dresser 16 is in precise tangential contact with the left-hand grinding wheel end, and so that the contoured portion 24 of the roll dresser 16 contacts the peripheral edge 28 of said left-hand grinding wheel 10. In this position the diamond inpregnated roll dresser 16 is preferably driven or rotated about its longitudinal axis and serves to face or dress the cylindrical portion of the left-hand grinding wheel 10. In order to avoid any tendency for the roll dresser 16 to itself become deformed, and to in turn create grooves or the like in the cylindrical end portion of the grinding wheel 10, the next successive step in practicing the method of the present invention comprises moving the tangential dresser roll 16 in a generally axially extending direction, as indicated by the arrow 34, along the area of tangential contact between the end portion 18 of the roll dresser and the corresponding cylindrical portion of the wheel 10 generally toward the right-hand wheel 12. After such movement, which may be somewhat less than the axial extent of the left-hand grinding wheel 10, the roll dresser 16 is then moved outwardly, and in a direction opposite the inward tangential direction referred to above, in the direction of the arrow 36 to remove the roll dresser 16 from contact with the left-hand grinding wheel 10.

In further accordance with the present invention, and in order to dress the right-hand grinding wheel 12, the roll dresser 16 is next moved generally parallel to the common axis of the grinding wheels 10 and 12 to an intermediate position (not shown) in the direction of the arrow 38 shown in FIG. 1. This intermediate position comprises a mirror image of the full line position shown in FIG. 1 for the roll dresser, that is, the dresser is spaced tangentially outwardly from the right-hand wheel 12 in this position. The above-described steps for dressing the left-hand wheel 10 are then carried out upon the right-hand wheel 12 for dressing it in a substantially similar manner to that referred to above. More particularly, the tangential roll dresser 16 is moved inwardly toward the righthand grinding wheel 12 so that the right-hand end portion 20 of the roll dresser contacts the right-hand wheel along its cylindrical portion, and so that the contoured roll portion 26 thereof contacts the peripheral edge 30 of the right-hand wheel 12. After being brought into tangential contact with the right-hand wheel 12, in a position corresponding to the broken line position shown in FIG. 1, the roll dresser 16 is moved axially along the tangential contact area between the right-hand end roll portion 20 and the right-hand wheel 12 toward the left hand wheel 10 as indicated by the arrow 40. The tangential roll dresser 16 is then moved outwardly in a direction opposite the inward tangential direction, as indicated by the arrow 41, to a position generally between the rest position shown in full lines in FIG. 1 and the intermediate position referred to above. Finally, the roll 16 is returned to the rest position by being moved generally axially in the direction of the arrow 44, wherein said dresser can be recycled if necessary to dress the coaxially arranged grinding wheels 10 and 12.

We claim:

1. A method for dressing the abrasive surfaces of coaxially arranged grinding wheels of the type used to grind opposed end portions of a workpiece in a centerless grinder, said method comprising the successive steps of moving a dresser roll tangentially inwardly and into tangential contact with at least an axially extending portion of one of said grinding wheels moving said dresser roll axially along said tangential contact area toward the other of said wheels to be dressed, moving said roll in a outward direction opposite said tangential direction, and again moving said roll parallel to the common axis of said wheels to a position wherein said roll can then be moved tangentially inwardly and then axially along the area of tangency between itself and said second wheel.

2. A method for dressing the abrasive surfaces of coaxially arranged grinding wheels of the type used to grind opposed end portions of a workpiece in a centerless grinder, said method comprising the successive steps of providing in a rest position a crush dresser roll with leftand right-hand cylindrical end portions and an intermediate portion of particular contour, moving the dresser roll tangentially inwardly so that the lefthand end portion thereof contacts one of said grinding wheels along an axially extending portion'thereof and said contoured roll portion contacts the peripheral edge of said wheel, moving said dresser roll axially along said area of tangential contact toward the other of said wheels, moving said roll outwardly in a direction opposite said inward tangential direction, moving said roll parallel the common axis of said wheels to an intermediate position wherein said right-hand roll portion is spaced tangentially outwardly from said other wheel, and moving said roll tangentially inwardly so that the right-hand end portion thereof contacts said other grinding wheel along an axially extending portion and said contoured roll portion contacts the peripheral edge of said roll.

3. The method according to claim 2 further characterized by the additional step of moving the dresser roll axially along said tangential contact area between said right-hand roll portion and said other wheel toward said one wheel.

4. The method according to claim 3 further characterized by the additional steps of moving the dresser roll outwardly in a direction opposite said inward tangential direction to a position generally between said rest and said intermediate positions thereof, and finally returning the roll to its rest position. 

1. A method for dressing the abrasive surfaces of coaxially arranged grinding wheels of the type used to grind opposed end portions of a workpiece in a centerless grinder, said method comprising the successive steps of moving a dresser roll tangentially inwardly and into tangential contact with at least an axially extending portion of one of said grinding wheels moving said dresser roll axially along said tangential contact area toward the other of said wheels to be dressed, moving said roll in a outward direction opposite said tangential direction, and again moving said roll parallel to the common axis of said wheels to a position wherein said roll can then be moved tangentially inwardly and then axially along the area of tangency between itself and said second wheel.
 2. A method for dressing the abrasive surfaces of coaxially arranged grinding wheels of the type used to grind opposed end portions of a workpiece in a centerless grinder, said method comprising the successive steps of providing in a rest position a crush dresser roll with left- and right-hand cylindrical end portions and an intermediate portion of particular contour, moving the dresser roll tangentially inwardly so that the left-hand end portion thereof contacts one of said grinding wheels along an axially extending portion thereof and said contoured roll portion contacts the peripheral edge of said wheel, moving said dresser roll axially along said area of tangential contact toward the other of said wheels, moving said roll outwardly in a direction opposite said inward tangential direction, moving said roll parallel the common axis of said wheels to an intermediate position wherein said right-hand roll portion is spaced tangentially outwardly from said other wheel, and moving said roll tangentially inwardly so that the right-hand end portion thereof contacts said other grinding wheel along an axially extending portion and said contoured roll portion contacts the peripheral edge of said roll.
 3. The method according to claim 2 further characterized by the additional step of moving the dresser roll axially along said tangential contact area between said right-hand roll portion and said other wheel toward said one wheel.
 4. The method according to claim 3 further characterized by the additional steps of moving the dresser roll outwardly in a direction opposite said inward tangential direction to a position generally between said rest and said intermediate positions thereof, and finally returning the roll to its rest position. 